Combination valve cap and tire gauge device



Dec. 24, 1940. w .5. WEST 2,225,675

COMBINATION VALVE CAP AND TIRE GAUGE DEVICE Filed Dec. 2. 1938 Patented Dec. 24, 1940 PATENT OFFICE COMBINATION VALVE CAP AND TIRE GAUGE DEVICE f William S. West, Chicago, Ill. Application December 2, 14938, Serial No. 243,618

3 Claims.

My invention relates to combination valve cap and tire gauge devices and it has for its object the provision of a new and improved form and arrangement of parts in devices of this type whereby a driver of a motor vehicle having one of my improved devices on each of the tires can by a glance at the several devices determine quick- 1y and easily whether pressure in the tires is normal or below normal.

To this end it is one of the objects of my invention to provide an improved device of the type specied adapted to be left in position on the valve stem in place of the ordinary cap and so arranged that regardless of the position of the wheel when it has come to rest, the condition of pressure in the tire can be ascertained at a glance without the necessity for manual manipulation of any of the parts.

It is another object of my invention to provide a device of this type which will weigh but little if any more than an ordinary valve cap and thus have a minimum effect of throwing the wheel out of balance when applied in place of the cap. To this end I have provided a device of this type which is of small size and is adapted to be constructed of light weight materials.

It is also an object of my invention to provide a device of this type which is of such small diameter as to be capable of being turned readily about its longitudinal axis for application to the threads of the valve stem of a tire.

It is a further object of my invention to provide a device of this type which may be constructed on a commercial scale at comparatively low cost.

With this in view -I have provided a device having but few parts all of which, excepting a spring, may be molded economically of suitable materials thereby avoiding machine or other costly finishing operations.

It is another object of my invention to provide a device of this type having a transparent zonal window completely therearound through which the movement of the indicating member of the device may be readily observed in any position of t the device on the valve stem.

The invention consists in the novel and improved constructions, arrangements, and devices to be hereinafter described and v c ed for carrying out the above stated objects and such other objects as will appear from the i'ollowlngV specilication of a certain preferred embodiment illustrated in the accompanyingfdrawing, wherein- Fig. 1 is a side view of a portion of an automobile wheel and a tire in position thereon vequipped with my improved device;

Fig. 2 is a side view on an enlarged scale of my rinproved device mounted on the valve stem of a Fig. 3 is a sectional view taken on the line 3-3 of Fig. 2; 5

Fig. 4 is a view similar to Fig. 3 but showing a changed position of the parts; and

Fig. 5 is a side view on a diiierent scale of my improved device mounted on the valve stem of a tire and having fastening means attached thereto l0 for preventing misplacement or theft of the dev ce.

Like characters of reference designate like parts in the several views.

Referring rst to Fig. 1 of the drawing, a disc l5 wheel of any approved type is shown at i0 and is provided with a rim Il on which is mounted a pneumatic tire I2. On the valve stem I3 with which the tire I2 is equipped-and which extends inwardly through the rim II is placed my im- 20 proved combination valve cap and tire gauge device I4.

My improved device comprises a sleeve I5 of molded opaque plastic material which is provided with an exterior striated portion I6 and an in- 25 ternal threaded portion I1. The portion I1 is adapted to be threaded onto the valve stem I3. The sleeve I5 is also provided with an internal ledge I8 having a central perforation or opening I9 therethrough. Positioned on the ledge 181s an 30 imperforate flexible diaphragm 2li having a crown portion 2l and a rim portion 22. The diaphragm is constructed of a highly flexible material such as gum rubber and is of such thinness that it is easily foldable upon itself. 'I'he rim portion 22 35 is clamped tightly against the ledge I8 by a sleeve 23 of molded transparent plastic material which fits within the sleeve I5 and bears on the rim portion.

The sleeve 23 is provided with a ledge 24 hav- 40 ing a central perforation or opening 25 therethrough. A cap member 26 of molded opaque plastic material ilts over the transparent sleeve 23 and provides a chamber 21 above the diaphragm. 'I'he cap member 26 and the opaque 45 sleeve I5 are separated by a narrow outwardly extending annular rib on the transparent sleeve 23 thereby providing a sight zone or window 28 entirely around the device through any portion of which a person may see into the chamber 21. 50

In the chamber 21 is provided a loose ttlng slide element 29 having a stem 30 which passes freely through the opening 25 into contact with the crown portion 2I oi the diaphragm. The element 2l is constructed of molded opaque plastic 55 material preferably colored. 'I'he slide element is provided with a boss portion 32 and the cap member is provided with an internal boss. portion 33. Yielding means in the form of a coil spring 34 is positioned in the chamber 21 between the cap member and the slide element over or around said boss portions and tends to move the slide element toward the diaphragm. The stem 38 is of such diameter with respect to the adjacent portion of the transparent sleeve that the crown portion of the diaphragm will readily fold upon itselffwhen the slide element moves toward the tire valve and the opposite side of the diaphragm is subject to the tire air pressure, in which case the parts are substantially as shown in Fig. 3.

In the threaded portion of the sleeve I and bearing against the bottom of the ledge I8, I have provided a gasket 38 having an outwardly projecting boss portion 31 and a central opening 38. As shown, the boss portion 31 is provided with a V-shaped groove 39 across its outer face. While I have shown this V-shaped groove 38, it is of course apparent that the passage 38 may open into the valve stem I3 through the side wall of boss portion 31 and the end of this boss portion closed to define means for engaging the pin 48 of the valve. The gasket is constructed of a rubberlike material sufficiently yieldable to provide an air-tight seal between it and the valve stem I3 when the device is tightly screwed on the valve stem, but of such stiffness that its boss portion holds the tire valve open by maintaining the valve pin 40 depressed against the action of the valve spring (not shown). i

The sleeves I5.and 23 and the cap member 26, are preferably held together by appropriate cementitious material applied between the parts. A solvent cement, such, for example, as acetate may be used between members I5, 23 and 26 with the result that in effect these members become as one. Due to the yieldability of the gasket 38, this member need not be cemented in as the friction between it and the sleeve threads is ample to hold it in place.

If desired, protection against loss of the device by misplacement or theft may be obtained by the arrangement shown in Fig. 5, in which a ring 4I surrounds the threaded valve stem and is so deformed that it is very diflicult-to remove. chain 42 connects the ring 4I with a ring 43. 'I'he ring 43 is rotatably but non-removably mounted on the device between the sleeves I5 and 23.

When my improved device is applied to the valve stem of the tire, the boss portion 31 depresses the valve pin 40 and the vair from the tire passes around the valve pin 40, through the openings 38 and I9, and is applied to the adjacent side of the diaphragm. The spring is of such strength that the large portion of the slide element is just above the window 28 and out of sight when the tire pressure is normal, say 30 lbs. When the air pressure in the tire drops appreciably below normal, the slide element under pressure of the spring moves toward the tire valve and its position with respect to the window indicates accurately the under inflation of the tire. By employing springs of different strength, the device may-.be adapted to lower or higher tire pressures. 4 l

The height of the crown portion ofthe diaphragm is such thatY when the tire pressure is normal the diaphragm f is not substantially stretched. Since the crown portion is foldable upon itself in the space between the stem 38 and the adjacent portion of the sleeve 23, the movable portion of the diaphragm oii'ers no appreciable inherent resistance to movement. The diaphragm acts simply as a floating air seal between the tire air pressure on one side and the slide element and spring on the other. The slide element iioats freely between the diaphragm and the spring without contacting the sleeve 23. The device is very sensitive, therefore, to changes in pressure within the tire and provides an accurate means of determining quickly when the pressure drops below normal.

I do not intend to limit my invention to the details of construction shown and described except only in so far as certain of the appended claims are specifically so limited as it will be obvious that modifications may be made without departing from the principles of the invention.

I claim: Y

1. In an arrangement for indicating the air pressure in a pneumatic tire, the combination of a housing, flexible imperforate means in said housing having crown and rim portions and having its rim portion sealed across the housing and dividing it into first and second chambers, the first chamber being adapted to be put into communication with the air chamber oi a tire, the crown portion of said flexible means extending into the second chamber, the second chamber having a sight zone, yielding means in the second chamber, and a slide element in the second chamber under the influence of said yielding means and having an indicator, said slide element being slidably movable in the second chamber and having a stem bearing on the outer side of said crown portion, said crown portion folding within itself around the stem of the slide element as the slide element moves toward the first chamber, said crown portion being of such length that it is not substantially stretched when unfolded and the slide element is at the limit of its movement in the opposite direction away from the first chamber.

2. In an arrangement for indicating the air pressure in a pneumatic tire, the combination of a sleeve adapted to be' connected with the valve stem of a tire and having an internal perforated ledge, an imperforate iiexible diaphragm extending across the sleeve and having crown and rim portions with the rim portion on said ledge, a second sleeve clamping said rim portion against said ledge to provide an air chamber under said diaphragm, a cap member on the second sleeve to provide a second chamber above said diaphragm, said crown portion extending into the second chamber, a slide element slidably movable inthe second chamber and having a stem portion bear-` element is at the limit of its movement inthe opposite direction away from the first chamber.

3. In an arrangement for indicating the air pressure in a pneumatic tire, the combination of an opaque sleeve adapted to be connected with the valve stem of a tire and having an internal perforated ledge, an imperforate flexible dla-I phragm extending across the sleeve and having crown and rim portions with the rim portion on said ledge, a second sleeve clamping said rim portion against said ledge to provide an air chamber under said diaphragm, an opaque cap member on the second sleeve to provide a second chamber above said diaphragm, said' crown portion extending into the second chamber, a slide element slidably movable in the second'chamber and havl" ingtwa stem portion bearing on the outer side of said crown portion, yielding means between said slide element and a wall on the second chamber for pressing the stem of said slide element against saidcrown portion, said second sleeve having a transparent portion, said opaque sleeve and cap member being separated to provide therebetween with the transparent portion of the second sleeve' WILLIAM S. WEST. 

